Hansen keen on next-generation nuclear power

Australian
Wednesday 10/3/2010 Page: 23

RENEWABLE energy won't save the planet so it's time to go nuclear, according to one of world's most high profile climate scientists. "We should undertake urgent focused research and development programs in next generation nuclear power," said atmospheric physicist James Hansen, head of NASA's Goddard Institute for Space Studies and adjunct professor at Columbia University's Earth Institute in New York.

While renewable energies such as solar and wind were gaining in economic competition with coal-fired plants, Professor Hansen said they wouldn't be able to provide baseload power for years to come. Even in Germany, which pushed renewables heavily, they generated only 7% of the nation's power. "It's just too expensive," said Professor Hansen, an expert in climate modelling, planetary atmospheres and the Earth's climate. "Right now, fossil fuels are the cheapest form of energy, except for operating nuclear plants," he said on the first day of a lecture tour in Australia.

According to Professor Hansen, because the threat of global warming was so serious, nations such as the US, China and even Australia must crank up support for so-called third and fourth generation nuclear systems. "Current nuclear plants are the second generation. The third generation is ready to build now," he explained, pointing to conventional light water reactors, which generated heat by the fission of uranium fuel. Two fourth generation technologies are on the drawing board. Fast reactors use liquid sodium metal as a coolant for the fission of metallic solid fuel, including existing nuclear waste and weapons grade uranium and plutonium.

Thorium reactors use fluoride salt as the medium for the energy producing nuclear reaction, so they don't require production of fuel rods. Professor Hansen admitted he was a late convert to advanced nuclear power. "But fourth generation solves two of the problems that made me sceptical," he said. "One is nuclear waste. It uses over 99% of the fuels, while second and third generations use less than 1%, leaving a waste pile with a half-life of 100,000 years. Fourth generation burns almost all the fuel and waste has a half life of decades." No commercial scale fourth generation plants exist, but seven nations, including Japan, France and China, have expertise or research and development projects. Which will get their first? "That's an open question,' according to Professor Hansen.